(a) under ISO Standard 9612:2009, Acoustics – Determination of occupational noise exposure – Engineering method:LEX,8h = LP,A,eqTe + 10 lg [Te/T0] dB,
where
Te = effective duration of the working day, in hours;
T0 = reference duration, 8 h;
(b) under CSA Standard Z107.56-13, 2014, Measurement of noise exposure:Lex,8h = Leq,t + 10 log (TW/8),
where Tw = effective duration of the working day, in hours;